U.S. patent number 4,949,652 [Application Number 07/371,340] was granted by the patent office on 1990-08-21 for waste disposal system.
Invention is credited to Henry H. Hadley.
United States Patent |
4,949,652 |
Hadley |
August 21, 1990 |
Waste disposal system
Abstract
This invention is directed at an infectious waste incinerator
system using primary and secondary combustion chambers to reduce
the waste to gaseous and particulate matter. Which is passed
through a waste heat recovery boiler reduces the temperature of the
gaseous and particulate matter and send the recovered heat to
pipes. The cooled gaseous and particulate matter is passed to a
baghouse packed-bed scrubber where the gaseous and particulate
matter is further cooled and diluted. The gaseous and particulate
matter is then passed to the lower end of a packed-bed scrubber
when it is passed to a treatment tank where it is subjected, in a
neutralizing compartment, to a hydroxide and is also surface
skimmed. The skimmed material is passed through a filter system and
then returned to the treatment tank. The gaseous treated material
is pumped back into the packed-bed scrubber and then out an exhaust
stack.
Inventors: |
Hadley; Henry H. (Lincoln,
MA) |
Family
ID: |
23463566 |
Appl.
No.: |
07/371,340 |
Filed: |
June 26, 1989 |
Current U.S.
Class: |
110/215; 110/210;
110/235; 96/136; 96/240 |
Current CPC
Class: |
B01D
53/68 (20130101); F23G 5/006 (20130101); F23J
15/006 (20130101); F23G 2202/103 (20130101); F23G
2205/10 (20130101); F23G 2206/10 (20130101); F23J
2215/30 (20130101); F23J 2217/101 (20130101); F23J
2219/40 (20130101) |
Current International
Class: |
B01D
53/68 (20060101); F23G 5/00 (20060101); F23J
15/00 (20060101); F23J 015/00 () |
Field of
Search: |
;110/215,235,210
;55/341,233,228,90,97,258 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bennet; Henry A.
Assistant Examiner: Ferensic; Denise L.
Claims
What I claim is:
1. A waste disposal system for controlled burning and safe disposal
of contaminated materials comprising a means of holding the
contaminated materials having a feed means associated therewith,
the feed means transporting the contaminated materials to an
incinerator chamber, the incinerator chamber providing a combustion
of the contaminated materials, the incinerator chamber in
communication with a bag filter which is connected to a packed
column scrubber, the packed column scrubber including a first
packed bed and a second packed bed and means of maintaining the bag
filter at a temperature above the dew point of HCl the first packed
bed in communication with the second packed bed, the packed column
scrubber having a sump tank connected thereto, an exhaust stack in
communication with the packed column scrubber for exhausting the
smoke from the packed column scrubber to an external environment,
the smoke substantially free of hazardous contaminants.
2. The waste disposal system as set forth in claim 1 wherein the
incinerator chamber further comprising primary and secondary
incinerator chambers, the feed means transporting the contaminated
materials to the primary incinerator chamber, the primary
incinerator chamber providing a primary combustion of the
contaminated materials, the primary incinerator chamber in
communication with the secondary incinerator chamber, the
incinerated material of the primary incinerator chamber passed to
the secondary incinerator chamber, the secondary incinerator
chamber providing a secondary combustion of the incinerated
material, the secondary incinerator chamber in communication with
the bag filter.
3. The waste disposal system as set forth in claim 2 further
comprising a heat exchange means, the heat exchange means
downstream from the primary and secondary incinerator chambers for
utilizing the heat therefrom, the heat exchange means in
communication with the bag filter.
4. The waste disposal system as set forth in claim 1 further
comprising a carbon filter, the carbon filter having an inlet and
an outlet, the inlet and outlet connected to the sump tank.
5. The waste disposal system as set forth in claim 1 further
comprising a condensable organic filter, the condensable organic
filter connected only to the sump tank.
Description
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to a waste disposal system and more
specifically to a waste disposal system for disposing of
contaminated medical waste material.
SUMMARY OF THE INVENTION
A waste disposal system for controlled burning and safe disposal of
contaminated materials comprising a means of holding the
contaminated materials having a feed means associated therewith,
the feed means transporting the contaminated materials to a primary
incinerator chamber, the primary incinerator chamber providing a
primary combustion of the contaminated materials, the primary
incinerator chamber in communication with a secondary incinerator
chamber, the incinerated material of the primary incinerator
chamber passed to the secondary incinerator chamber, the secondary
incinerator chamber providing a secondary combustion of the
incinerated material, the secondary incinerator chamber in
communication with in communication with a bag filter which is
connected to a packed column scrubber, the packed column scrubber
in communication with a secondary scrubber having a sump tank
connected thereto, an exhaust stack in communication with the
packed column scrubber for exhausting the smoke from the packed
column scrubber to an external environment, the smoke substantially
free of hazardous contaminants.
BRIEF DESCRIPTION OF THE DRAWINGS
Further details are explained below with the help of the example(s)
illustrated in the attached drawings in which:
FIG. 1 is a schematic view of a waste disposal system for
controlled burning, useful heat output and safe disposal of solid
contaminated medical waste materials according to the present
invention;
FIG. 2 is an isometric schematic drawing of the waste disposal
system for controlled burning, useful heat output and safe disposal
of solid contaminated medical waste materials shown in FIG. 1;
and
FIG. 3 is an isometric schematic drawing (partly broken away) of
the lower downstream portion of the waste disposal system for
controlled burning, useful heat output and safe disposal of solid
contaminated medical waste materials shown in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
There is shown in the drawings a waste disposal system 10 for
controlled burning, useful heat output and safe disposal of solid
contaminated medical waste materials. The waste disposal system 10
comprises a ram feeder 12 as part of a Simonds Model AF-4B
infectious waste incinerator which includes a primary incinerator
chamber 14, an afterburner or secondary incinerator chamber 16, a
waste heat recovery boiler 18, and an ash disposal system (not
shown). The pneumatically operated ram feeder 12 feeds an average
of 140 pounds of contaminated materials into the primary
incinerator chamber 14 every ten minutes, giving a cumulative,
maximum feed rate of 850 pounds of contaminated materials per hour.
The primary incinerator chamber 14 provides a primary combustion of
the contaminated materials utilizing temperatures of around 1350
degrees F. This temperature burns the contaminated materials
creating as oxidation products HCl, H.sub.2 O in the form of steam,
CO.sub.2, metallic oxides and a residue of organic gases. The
primary incinerator chamber 14 is in communication with a secondary
incinerator chamber 16. The incinerated material gases and
particulate matter from the primary incinerator chamber 14 is
passed to the secondary incinerator chamber 16. The secondary
incinerator chamber 16 using temperatures in the range of 1600-2000
degree F. provides a secondary combustion of the incinerated
material from the primary incinerator chamber 14. This temperature
burns the contaminated materials creating as oxidation products
HCl, H.sub.2 O in the form of steam, CO.sub.2, metallic oxides and
a residue of organic gases. The secondary incinerator chamber is in
communication with the waste heat recovery boiler, a York Shipley
Model No. HRH 750 heat recovery boiler, downstream thereof, as
shown in FIG. 2, which reduces the heat from the primary and
secondary combustions (exhaust gases) from a temperature of 1800
degrees F. to 400 degrees F. when they exit. The recovered heat
from the waste heat recovery boiler 18 is used to create steam
which can be used in hospital steam pipes for example. A bypass
line upstream of the heat recovery boiler will be used during
boiler shutdown or emergency periods to duct exhaust gases to a
bypass stack. The bypass line is to be utilized during emergencies
only. The gaseous secondary combustion material is passed through a
model SS64PJ Wickberg stainless steel bag house 20. The bag house
20 has an air handling capacity of 5000 scfm at 4 inches of of
water column. The gaseous secondary combustion material entering
the bag house 20 is diluted and cooled by an adjustable inlet air
damper (not shown) to maintain the bag house 20 air inlet
temperature at 400 degrees F. The temperature within the bag house
20 is maintained above the dew point of Hydrogen Chloride. The bag
house 20 includes 64 filter tubes (not shown) formed of an isaramid
such as Nomex, a trademark of the Dupont Company. Each of the
filter tubes has an effective surface area of 12.5 square feet to
give a surface area of 800 square feet. The filter tubes are jet
pulse cleaned in groups of eight every sixty seconds. Soot from the
jet pulse cleanings will be collected in an inverted pyramidal
hopper 21 having a volume of 24 cubic feet. The gaseous secondary
combustion material is discharged from the bag filter 20 through a
duct into an Ambi, Inc. custom-made, horizontal, packed-bed
scrubber 22 rated at 3400 actual cubic feet per minute capacity at
175 degrees F. The duct from the bag filter 20 to the scrubber 22
includes an internal spray means 41 whose operation will be
setforth hereinafter. The scrubber 22 has a length of 10.6 feet and
a cross sectional area of 14.5 feet and includes two Kimre
packed-beds namely, a first packed bed 23 and a second packed bed
25, a demister 27 and four spray heads covering each of the packed
beds. The packed column scrubber 22 is communicatively connected at
its lower end and at it central portion by drain pipes 31 with a
treatment tank 24. The scrubber 22 at its exit end communicates
with an exhaust stack 32. The treatment tank 24 includes a
neutralizing compartment 34, which has a sump tank 28 connected
thereto into which the two drain pipes 31 exhaust. A first pump 35
(see FIG. 3) pumps an aqueous solution of 10 percent by weight of
sodium hydroxide into the neutralizing compartment 34. A main pump
36 is connected between the neutralizing compartment 34 and the
base and the central portion of the packed column scrubber 22 as
shown in FIG. 3. The neutralizing compartment 34, as shown in FIG.
3 has a skimmer 37 operating on the surface which communicates with
a filter system 39. The filter system 39 comprises a condensable
organic filter 38 and a second pump 40. The condensable organic
filter may be a carbon filter. The second pump 40 moves the
material skimmed from the neutralizing compartment 34 through the
filter 38 removing organic material as particulate matter floating
on the surface of the neutralizing compartment 34. An NaCl bleed 29
is position on the base of the sump tank 28 to keep the
concentration of NACL from becoming too great. The gaseous
secondary combustion material as it is cleaned by the packed column
scrubber 22 forms a liquid material and at the lower end of the
packed column scrubber 22, the liquid material is caused to
discharge, by the action of the main pump 36, into the treatment
tank 24. The secondarily scrubbed and filtered gaseous tertiary
combustion material (ie. The remaining combustion material after it
has gone through the primary incinerator chamber 14, the secondary
incinerator chamber 16, the waste heat recovery boiler 18, the bag
house 20 and the first packed bed 23) is passed into the middle
portion of the packed column scrubber 22 and is then drawn into the
exhaust stack 32 by action of the blower 30 located within the
exhaust stack 32. The thoroughly cleansed gaseous tertiary
combustion material is then exhausted to an external environment
substantially free of hazardous contaminants.
* * * * *